Calibration

After setting Parameters, the scanner must be calibrated before running a scan.

Calibration optimizes image quality by creating an Offset filter to correct for background radiation, and a Gain filter to correct for variations within the detector panel.

Before calibration, make sure you have saved the "Acquire Position" by clicking the Save button in the CNC portion of the toolbar. Move the specimen out of the field of view and turn off the x-rays. To begin calibration, click the "detector calib" button in the Detector portion of the toolbar, which is shown here. For most scans, the Auto box should be checked, which will run both a Offset and Gain, and 2 Points should be used. The default for Average is 100 and for Skip is 10.

After calibration has been run, the panel should display an even, though likely noisy, picture without any shadow images, lines, etc. Calibration must be rerun before scanning if voltage, current, or filters were changed. To bring the sample back into view, click Move to in the CNC portion of the toolbar and "Acquire Position."